Pi - Examples, Exercises and Solutions

There are only 4 radii in a circle.

A radius is a straight line that connects the center of the circle with a point on the circle itself.

Therefore, the answer is incorrect, as there are infinite radii.

False

Which diagram shows a circle with a point marked in the circle and not on the circle?

The interpretation of "in a circle" is inside the circle.

In diagrams a'-d' the point is on the circle, and in diagram c' the point is outside the circle.

Is it possible that the circumference of a circle is 8 meters and its diameter is 4 meters?

To calculate, we will use the formula:

$\frac{P}{2r}=\pi$

Pi is the ratio between the circumference of the circle and the diameter of the circle.

The diameter is equal to 2 radii.

Let's substitute the given data into the formula:

$\frac{8}{4}=\pi$

$2\ne\pi$

Therefore, this situation is not possible.

Impossible

Is there sufficient data to determine that

$GH=AB$

No

M is the center of the circle.

Perhaps $AB=CD$

No

In which of the circles is the center of the circle marked?

M is the center of the circle.

Perhaps $MF=MC$

Yes

M is the center of the circle.

In the figure we observe 3 diameters?

No

M is the center of the circle below.

$AB=10$

Can a chord with a length of 15 cm be drawn in the circle?

No

M is the center of the circle shown below.

AB is a chord in the circle and is 8 long.

Which of the options is a reasonable length for circle's diameter?

$16$

M is the center of the circle.

Perhaps $CM+MD=2EM$

Yes

Perhaps $MF+MD=AB$

No

M is the center of the circle.

Is AB the diameter?

No

M is the center of the circle.

Perhaps $0.5DC=EM$

Yes

Perhaps $P=\pi\times EF$

Yes